There by the high road he got himself up as a Daoist with a broken leg, blood dripping down his foot, groaning and moaning, crying only: “Save me! Save me!”

妝做 (zhuāng zuò), “to disguise oneself as, to feign being.” 跌折腿 (diē zhé tuǐ), “to have fallen and snapped a leg.” 哼哼 (hēng hēng) renders the sufferer's moaning — the pose completes the trap the disguise began.

Now Tripitaka, relying on the Great Sage Sun and Sha Monk, came happily along.

仗著 (zhàng zhe), “leaning on, with the backing of” — the durative 著 (zhe) of continued reliance. With his two guardians at hand, the master travels without fear — the very security the demon means to exploit.

Just as they went, they heard a cry: “Master, save me!”

正行處 (zhèng xíng chù), “just as they were going along.” 聽得 (tīng de), “heard” — the potential-resultative 得 (de); the cry is now framed as the pilgrims hear it, addressed to the “Master.”

Tripitaka heard it and said: “Merciful Heaven, merciful Heaven! In these wild hills, with never a hamlet on any side — who can be crying? Surely someone frightened witless by tigers, leopards, wolves, or serpents.”

善哉 (shàn zāi), “how good! / merciful indeed,” a Buddhist exclamation of compassion. 諕 (xià) is the loan-graph for 嚇, “to frighten”; 諕倒, “scared into collapse.” The master's first instinct is pity, not suspicion.

The Elder reined his fine horse around and called: “Who is it that's in distress? Come out.”

兜回 (dōu huí), “to rein about, to turn (a mount) back.” 有難者 (yǒu nàn zhě), “one in distress, one met with calamity” — 難 read nàn, “trouble, peril,” not nán, “difficult.” 甚人, “what person, who,” the interrogative shén.